SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7dd0ec70ab643b511db004062e0f9fc4898eb2bc9bd584c4cf43bf3515d78359' 
  AND token = 'VMSmXeVcLZrRktvBrjSwMpmqX3bLPq9qszQYDjjyoiM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}